Before I can make more progress learning about mushrooms, I need to learn some vocabulary and a few concepts. I've already learned that mushrooms are the fleshy, spore-bearing fruiting bodies of certain fungi. Fungi is in its own biological kingdom, separate from plants and animals. The visible mushroom is only a small part of the larger organism, most of which is an underground network of thread-like filaments called mycelium.
But I need some more information about mushroom parts, types, and forms. This will help me describe what I'm seeing, and then identify what I'm seeing. I'm starting small, and will continue to learn more as I go.
Mushroom Parts
First, some basic mushroom parts. Mushrooms come in many shapes and sizes with endless variations, but the following diagram shows some of the common parts (see the definitions below). Knowing these parts and their purpose is a good place to start.
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| Parts of a Mushroom (illustration by Zhousun21, based on public domain art) |
Parts Defined
- Cap: the structure on top of the mushroom that contains the gills or pores. Mushroom caps come in different sizes, shapes, colors, and textures. They can be smooth, covered with scales, or have teeth.
- Cap Undersides: cap undersides can be in the form of gills, teeth, ridges, or pores (the illustration shows gills). The purpose of these structures is to produce and release spores, which are used by fungi to replicate. Gills may be made of one or two layers: the lamellae that reach from the stem to the edges, and lamellulae that are shorter gills that don't reach the stem.
- Stem or Stipe: the stalk of the mushroom. Its primary function is to support the cap and the spores it contains.
- Scales: rough patches, flakes, or shaggy patterns of tissue found on the surface of the cap. Scales form hard-shelled protection for fungi, and can be used for identification. They typically appear on the mushroom cap but can be present on the stem.
- Ring or Annulus: some mushrooms develop a partial veil that surrounds and protects the underside of the cap. As the mushroom develops, the partial veil, or annulus, breaks away and is left hanging around the stem.
- Volva: other types of mushrooms develop a universal veil that encapsulates the entire mushroom during development. As the mushroom matures, the universal veil breaks off. Pieces of the veil, or volva, remain attached to the bottom of the stem.
- Mycelial Threads: an underground network of hyphae (or branching filaments that make up the mycelium). Their primary function is to collect nutrients and water. When conditions are right, mycelium may produce a mushroom.
Mushroom Cap Shapes
The mushroom cap shape is an important feature for describing and identifying mushrooms.
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| Mushroom Cap Shapes (art by Real Mushrooms®) |
Basic Cap Shapes
- Conical: caps that form a cone, hood, or pointed helmet shape, often tapering to a point at the top.
- Campanulate: caps that are shaped like a bell — narrow at the top, widening toward the edges, with a rounded crown and curved sides. The "bell-shaped" structure often features a central, slight bulge and is a common, distinct profile.
- Ovate: caps that have an egg-shaped form, resembling half of an egg or a rounded oval.
- Flat: caps that are spread out, horizontal, or disc-like rather than domed, conical, or umbrella-shaped. This shape can indicate a mature growth stage, a specific species type, or a bracket-like growth habit.
- Infundibuliform: caps that are funnel-shaped, vase-shaped, or deeply depressed in the center. The shape resembles a cone or a chalice, with the edges often raised and the middle dipping significantly downward.
- Convex: caps that have a smoothly rounded, domed, or umbrella-like appearance. They resembles an inverted bowl or a gentle curve, and it is one of the most common shapes for young mushrooms and agarics. ("Agarics" refers to fungi with fruiting bodies that resemble an ordinary mushroom, having a convex or flattened cap with gills on the underside).
- Depressed: caps where the center of the cap is lower than the surrounding area, creating a concave, bowl-like, or sunken appearance.
- Umbilicate: caps that feature a small, distinct, navel-like depression or "innie" hole right in the center.
- Umbonate: caps that feature a raised bump, knob, or "outie" protuberance in the exact center.
Mushroom Cap Undersides
The mushroom cap underside is another important feature for describing and identifying mushrooms. The purpose of the undersides is to deliver spores, so they are adapted to do so in their specific environment.
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| Mushroom Cap Undersides (art by Real Mushrooms®) |
Basic Mushroom Cap Undersides
- Gills (or lamellae): thin, papery, blade-like structures on the underside of a mushroom cap that radiate from the stem, and maximize surface area for spore production and dispersal. They contain spore-producing cells called basidia and are categorized by shape, density, and attachment type. The gills may not touch the stem (free); be broadly attached to the stem (adnate); run down the length of the stem (decurrent); or reach the stem and turn upwards, attaching with a narrow point (adnexed). Gill spacing can be crowded, close or distant. Edges may be smooth, serrated, or uneven.
- Teeth (also called spines or hydnoid structures): a specialized spore-bearing surface found on the underside of certain fungi, serving as an alternative to gills or pores. They are long, thin, shaggy, or icicle-like projections that hang down from the mushroom cap and house the hymenium (spore-producing layer). Spores are released from their tips. Examples include Lion's Mane, Hedgehog, and Coral Tooth mushrooms.
- Ridges (also called false gills): a type of spore-bearing surface found on the underside of certain mushroom caps (and sometimes down the stipe toward the ground), distinguishing them from true gills, pores, or teeth. They look like raised veins, shallow wrinkles, or blunt, thick folds rather than thin, papery sheets. They are not easily detached from the cap, and seem to be part of the mushroom flesh itself. Like gills, their purpose is to increase surface area to produce, store, and disperse spores. The most well-known examples of mushrooms with ridge structures are Chanterelles.
- Pores: the downward-facing, sponge-like openings of a poroid hymenophore, consisting of tightly packed vertical tubes under the cap that house spore-producing tissue. Unlike gills, these tubes protect developing spores, releasing them through the pore mouths when mature, common in boletes and polypores. Pore size, shape, color, and density vary by species, and are used for identification.
Common Mushroom Groups
Following is a list of common mushroom groups. I'm not providing details, but the list will be handy as I encounter different types of mushrooms. I already recognize some of these names from our Over-the-Hills Gang hikes, and from a recent Mushroom Exhibition that I attended at the Tilden Nature Area. Some types are familiar from the kitchen.
- Gilled Mushrooms
- Boletes
- Polypores
- Bracket fungi
- Chanterelles
- Puffballs
- Cup Fungi
- Corals
- Stinkhorns
- Jelly fungi
- Earthstars
- Earth Tongues
- Morels
- Truffles
- Crusts
- Lichen
- Yeasts
- Smuts
- Bunts
- Rusts
Learn More
There are many wonderful sources out there for learning more about mushrooms. Following are some resources that I'm finding useful. Another great resource is the iNaturalist app, available on Google Play and the App Store.
- Mushroom Appreciation - blog about North American mushroom species. Includes recipes.
- Mushroom Classification - Mushroom Identification. Amazon Storefront.
- Mushroom Morphology - Mushroom Identification. Amazon Storefront.
